Reversed SM465 as overdrive

So i have been researching this old idea, backing a 465 with a second one, run backwards. That 1.70:1 gear would make a 0.59:1
Mating the tails of a pair of 2wd 465s is simple. The challenge is getting the input of the rear one to run a driveshaft.
But Spicer makes a yoke that fits on the $89 MD-465 1.5" input, and takes a 1410 u-joint. And it's only $45. The Spicer part number is 3-4-6561-1.
If. I ever do it, I'll post pics somewhere on the net, depending on where i don't get ridiculed for it. Pirate4x4 already failed.


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I've not familiar with this idea. What is the goal?
What is the goal? for old 4 speeds to get a OD this is a slick way to do it, (about $1600 More than your idea...)
This mounts between the bellhousing and transmission, so the transmission would move back a few inches.

I have never been in a sm465, but I have been in a np435. 1st and R are straight cut gears, 2,3,4 are helical(?), not sure if that has any thing to do with running at high speed or backwards...

To what end?
Having it constantly in the second 465's 2nd gear? Thus overall raising your final drive ratio? Just re-gear the axle

If not that ^^^ you plan to shift it between the 2nd 465's 3rd (1:1) gear, and then into its 2nd gear once you need OD?
So a 2nd shifter coming up from nearly the back seat since the 465 isn't a linkage trans?
Going to compression shift it without a clutch? With the synchros going backwards? Synchronizers are designed to work with the shaft spinning forwards, and the input (now output) shaft being disconnected via clutch to match the main shaft, and counter shaft speeds.

To save money?
By the time you buy a second trans, the various yokes/joints, mounts, and then modify both driveshafts for the length. I'd imagine you're just barely shy of buying a legit, and superior OD trans like an NV, or OD box. . .all to have a janky, cobbled together system. That is needlessly long and messing with pinion angle. And if you intend to use this on a 2wd vehicle, one less driveshaft. But that also opens up the available OD transmissions considerably.

Or is it just for the "weird" factor? Or the "want to see if i can do it" factor? - i actually respect that.

There really is a reason this isn't already a "thing"
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